Ph.D. in Marine Biology
from the Scripps
Institution of Oceanography (U.C. San Diego),
specializing in marine animal physiology and biochemistry,
especially thermal, pH and osmotic adaptations, with Dr.
George Somero.

Talks given in
many U.S. states, and in Canada, England, Scotland,
Belgium, Switzerland, Japan, New Zealand, Botswana
and Brazil on
marine and medical research; students have given research
presentations at many meetings in the U.S. and in Russia,
France, Australia, Iceland,
and New Zealand.

.In the submersible Alvin (2006);
on the SEA Semester sailing ship at Moorea, French Polynesia
(2013);
with a supergiant amphipod from the Mariana Trench (2014)

TEACHING
(Semi-Retired) & ONLINE RESOURCES:Prof. Yancey, for 35 years, taught
many courses--especially PHYSIOLOGY*,
MARINE BIOLOGY and BIOETHICS. He has now retired
from full-time teaching, but will continue to have research
students for their research thesis requirement..
He will also continue to maintain educational websites. See
links below for student research and those sites:

*Dr.
Yancey is a co-author of a 2005 (1st ed.) and 2013 (2nd ed.)
TEXTBOOK:

RESEARCH:Prof. Yancey's research is
described below, with additional information found by clicking
the blue topics:

OVERVIEW
Most of the research in Prof.
Yancey's laboratory focuses on Organic
Osmolytes: compounds that cells accumulate
under dehydrating osmotic stress. Such stresses include high salinity
(as in seawater, or in the interior of mammalian kidneys), evaporation
(as in deserts), freezing, dietary
imbalances, and diseases (e.g., high glucose
in diabetes mellitus). Organic osmolytes can be built up in
cells to reduce osmotic water loss; and, unlike salt ions, they
do not disrupt cellular macromolecules. Moreover, many osmolytes
have cytoprotective properties such as stabilizing proteins
against denaturing agents like urea, temperature, and pressure
in the deep sea.

Trimethylamine
oxide (TMAO)Hypotaurine
[add O or an SH to the S-group to
form taurine or thiotaurine, respectively]

DETAILS:
Prof. Yancey and others have found that some osmolytes, especially
methylamine types such as TMAO
(left), can actually stabilize
proteins and counteract destabilizing effects of
perturbants such as urea, salt, temperature and pressure. TMAO
has a breakdown product, TMA (trimethylamine), that makes marine
animals smell "fishy." Methylamines are high and appear to protect
proteins in
i) sharks and
relatives, which also have the perturbing
compound urea as an osmolyte;
ii) mammalian (including human) kidneys,
which must concentrate urea as a perturbing waste;
iii) deep-sea animals which
must cope with protein disturbances from high pressure.
Our discovery of TMAO's role in the deep sea was featured in a New
Scientist news story in 1999 and in a 2012
cover story of Science News. See Deep-sea
Fish page for pictures and Deep-Sea
Research page for research details.

--Stabilizing properties of osmolytes may have practical
applications, e.g., Welch and colleagues have shown
that TMAO and other osmolytes can prevent the damaging protein of
"mad-cow" disease from forming, and can cause the malformed
protein of cystic fibrosis to fold properly. (Dr. Yancey
assisted in one of the latter studies; see Howard et al.
reference below in Research Area 2.)

--We are also studying the role of osmolyte-type solutes in
animals at hydrothermal vents and gas
seeps, which have high
levels of hydrogen sulfide, a gas toxic to most animals. A major
osmolyte in shallow-water marine invertebrates such as clams and
crabs is taurine. Taurine is
also essential for mammalian brain development, and is the primary
ingredient in many so-called energy or sports drinks (hint: the
name taurine is derived from Taurus [bull]). Researchers in France
have found high levels of the taurine derivatives hypotaurine
and thiotaurine in clams, mussels and tubeworms
which have sulfide-oxidizing bacterial symbionts. Thiotaurine, a
product of hypotaurine and sulfide, may be a mechanism to prevent
sulfide toxicity. We have found hypotaurine and thiotaurine in
vent snails, limpets and heat-loving paralvinellid worms without
symbionts, and shown that thiotaurine levels vary with sulfide
exposure in these animals kept in laboratory pressure chambers.
See Seeps and Vents page for
pictures and Deep-Sea Research
Page for research details.

--Other researchers have found that the common osmolyte of marine
algae, DMSP
(dimethylsulfonoproprionate), breaks down into the gas DMS
(dimethylsulfide), which is largely responsible for the "smell of
the sea" that evokes emotional responses to the ocean. DMS is also
thought to trigger the seeding of clouds,
in what may be a global temperature negative feedback process.
This is one of the postulates of the so-called Gaia
hypothesis, which suggests that global warming will cause more DMS
production, which via cloud formation may cool the planet.
-- We have recently been working on DMSP and other osmolytes in coral
animals and their symbionts, with Dr.
Mary Hagedorn,who
is hoping to cryopreserve coral larvae for potential re-seeding
of decimated reef habitats.

A. REVIEW ARTICLES on osmotic
balance and cytoprotection using osmolytes (RED = recommended
reading for overview on osmolytes)
[Primary research articles are below]:

Somero, G.N., P.H. Yancey
(1978). Evolutionary adaptations of Km and kcat values:
fitting the enzyme to its environment through modifications
in the amino acid sequences and changes in the solute
environment of the cytosol. Symp. Biol. Hungar. 21:
249-276.